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Multiphysics simulation and optimization of the in-situ beneficiation process of ilmenite minerals from lunar regolith

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Science China Earth Sciences 2025年第1期68卷 195-207页

作者： Peng ZHANG Xin LIU Guanghui LIU wei DAI Hanzhe YANG Haibo ZHENG Zhi WANG Ran NIU Yifan BAI Yang ZHANG Chengbao LIU Ge YANG Junwei YANG Guang ZHANG Technology and Engineering Center for Space Utilization Chinese Academy of Sciences Beijing Hegong Simulation Co. Ltd

The exploration and utilization of lunar resources have become the major objectives of future lunar exploration missions. The classified collection and processing of lunar minerals is the basic prerequisite for the in-situ exploration and utilization of lunar resources. In this study, we propose a scheme for in-situ separation of magnetic minerals from lunar soils using the dry magnetic separation method. The scheme can realize the purpose of separating magnetic minerals from lunar regolith by altering the motion trajectory of lunar regolith particles with different magnetic properties. Detailed modeling of the dry magnetic separation device is conducted, and the three-dimensional distribution of magnetic parameters is calculated and analyzed. Based on the characterization and analysis of the chang E-5's samples, the morphologies and physical parameters of lunar regolith particles are modeled and simulated. A discrete element simulation of the motion process of lunar regolith particles under multi-physical field conditions is performed, and the influences of key parameters on the beneficiation performance of lunar magnetic minerals are investigated. Our results indicate that optimal separation and beneficiation of lunar regolith particles can be achieved under specific conditions of magnetic field strength and drum speed. Additionally, we analyze the effects of lunar weak gravity conditions and the charged nature of lunar particles on the beneficiation process, showing that these factors can obviously enhance the beneficiation process of lunar ilmenites. This study demonstrates the feasibility of using the dry magnetic separation method for the beneficiation of magnetic minerals from lunar regolith, providing a theoretical basis for the scientific tasks of collecting, processing, and utilizing lunar mineral resources.

关键词： Lunar regolith In-situ resource utilization Magnetic separation Classified sampling

Impacts of the COVID-19 pandemic on vegetable production and countermeasures from an agricultural insurance perspective

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Journal of Integrative Agriculture 2020年第12期19卷 2866-2876页

作者： GU Hai-ying WANG chang-wei Antai College of Economics and Management Shanghai Jiao Tong UniversityShanghai 200030P.R.China Institute of Industry Research Shanghai Jiao Tong UniversityShanghai 200030P.R.China Institute of Finance and Economics Shanghai University of Finance and EconomicsShanghai 200433P.R.China

In the face of the corona virus disease 2019(COVID-19)pandemic,it is essential to stabilize the security of urban“shopping baskets”.Through a survey and interviews with 46 agricultural cooperatives in Shanghai,this paper analyzes the impact of the pandemic on vegetable production and offers suggestions on agricultural *** research results show that:(1)the pandemic has impacted almost all stages of the vegetable supply chain but has had a greater impact on the sales stage;(2)the market risks of vegetable production have increased significantly,and the gap between the field price and the market price has *** sales price difference between traditional channels and e-commerce is notable;(3)farmers’incomes have generally declined due to the COVID-19 pandemic,and traditional small-scale farmers have suffered more losses;and(4)agricultural insurance plays an important role in stabilizing the supply of vegetables to the *** minimize the impact of the pandemic on vegetable production and to stabilize both urban“shopping baskets”and farmers’incomes,it is necessary to further improve agricultural insurance,especially to provide insurance against market risks.

关键词： COVID-19 vegetable supply chain agricultural insurance market risks

A review on the structure-performance relationship of the catalysts during propane dehydrogenation reaction

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Petroleum Science 2022年第2期19卷 819-838页

作者： Bohan Feng Yue-chang wei wei-Yu Song Chun-Ming Xu State Key Laboratory of Heavy Oil Processing College of ScienceChina University of PetroleumBeijing102249People's Republic of China

Dehydrogenation of propane(PDH)technology is one of the most promising on-purpose technologies to solve supply-demand unbalance of *** industrial catalysts for PDH,such as Pt-and Cr-based catalysts,still have their own limitation in expensive price and security ***,a deep understanding into the structure-performance relationship of the catalysts during PDH reaction is necessary to achieve innovation in advanced high-efficient *** this review,we focused on discussion of structure-performance relationship of catalysts in *** on analysis of reaction mechanism and nature of active sites,we detailed interaction mechanism between structure of active sites and catalytic performance in metal catalysts and oxide *** relationship between coke deposition,co-feeding gas,catalytic activity and nanostructure of the catalysts are also *** these discussions on the relationship between structure and performances,we try to provide the insights into microstructure of active sites in PDH and the rational guidance for future design and development of PDH catalysts.

关键词： Dehydrogenation of propane Metal catalysts Oxide catalysts Structure-performance relationship Active site Reaction mechanism

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Journal of Electronic Science and Technology 2021年第1期19卷 1-5页

作者： Zi-wei Wang Chi-chang chang Quan Zou The Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 610054 the School of Medical Informatics Chung Shan Medical UniversityTaichuang 40201 Medical University Hospital Taichung 40201

The outbreak of coronavirus disease 2019(COVID-2019)has drawn public attention all over the *** a newly emerging area,single cell sequencing also exerts its power in the battle over the *** this review,the up-to-date knowledge of COVID-19 and its receptor is summarized,followed by a collection of the mining of single cell transcriptome profiling data for the information in aspects of the vulnerable cell types in humans and the potential mechanisms of the disease.

关键词： Coronavirus disease 2019(COVID-19) bioinformatics data mining single cell sequencing

Recent progress on photoactive nonprecious transition-metal complexes

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Science China Chemistry 2025年第1期68卷 46-95页

作者： Zhong-Liang Gong Hong-Jie Zhang Yan Cheng Jianxun Liu Yuhan Ai Yaqin Li Zhihui Feng Qiong Zhang Shaolong Gong Yong Chen chang-Jiang Yao Yuan-Yuan Zhu Liang-Jin Xu Yu-Wu Zhong CAS Key Laboratory of Photochemistry Institute of Chemistry Chinese Academy of Sciences State Key Laboratory of Structural Cemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences School of Chemistry and Chemical Engineering Anhui Key Laboratory of Advanced Catalytic Materials and Reaction EngineeringHefei University of Technology State Key Laboratory of Explosion Science and Safety Protection School of Mechatronical Engineering Beijing Institute of Technology College of Chemistry and Molecular Sciences Hubei Key Lab on Organic and Polymeric Optoelectronic Materials Wuhan University School of Chemistry and Chemical Engineering Anhui University Key Laboratory of Photochemical Conversion and Optoelectronic Materials & CAS-HKU Joint Laboratory on New Materials Technical Institute of Physics and Chemistry Chinese Academy of Sciences

Photoactive complexes of nonprecious transition metals, mainly including those in the first-row and partially the second-row of the Periodic table of elements, have received increasing attention in view of their low cost and long-term sustainability. They are recognized as promising alternatives to noble transition metal complex congeners that have been extensively studied in optoelectronic devices, artificial photosynthesis, photocatalysis, biodiagnostics, and therapeutics, etc. This review is devoted to a comprehensive summary on the classical and recent advances on photoactive nonprecious transition metal complexes, including photoactive Zr, V, Cr, Mo, and W complexes, Mn complexes and hybrids, Fe, Co, Ni, and Cu complexes, and Zn and Cd complexes and hybrids. A particular focus is given on the molecular design, modulation of photophysical and photochemical properties, and applications of the representative and lately-developed nonprecious metal complexes. In addition, a perspective on the future development in this field is provided at the end of this review.

关键词： photoactive metal complexes earth-abundant metals nonprecious metal complexes luminescence photochemistry

Validity of extracting photoionization time delay from the first moment of streaking spectrogram

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Chinese Physics B 2019年第1期28卷 330-339页

作者： chang-Li wei Xi Zhao School of Physics and Electronics Qiannan Normal College for Nationalities Department of Physics Kansas State University

Photoionization time delays have been studied in many streaking experiments in which an attosecond pulse is used to ionize the atomic or solid state target in the presence of a dressing infrared laser field. Among the methods of extracting the time delay from the streaking spectrogram, the simplest one is to calculate the first moment of the spectrogram and to measure its offset relative to the vector potential of the infrared field. The first moment method has been used in many theoretical simulations and analysis of experimental data, but the meaning of this offset needs to be investigated. We simulate the spectrograms and compare the extracted time delay from the first moment with the input Wigner delay. In this study, we show that the first moment method is valid only when the group delay dispersions corresponding to both the spectral phase of the attosecond pulse and the phase of the single-photon transition dipole matrix element of the target are small. Under such circumstance, the electron wave packet behaves like a classical particle and the extracted time delay can be related to a group delay in the photoionization process. To avoid ambiguity and confusion, we also suggest that the photoionization time delay be replaced by photoionization group delay and the Wigner time delay be replaced by Wigner group delay.

关键词： photoionization time delay strong laser field attosecond science first moment

Vegetable/fruit, smoking, glutathione S-transferase polymorphisms and risk for colorectal cancer in Taiwan

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World Journal of Gastroenterology 2005年第10期11卷 1473-1480页

作者： Chih-ching Yeh Ling-Ling Hsieh Reiping Tang Chung Rong chang-Chieh Fung-chang Sung Institute of Environmental Health Department of Public Health Colorectal Section

AIM: To investigate the colorectal cancer risk associated with polymorphic GSTM1, GSTT1 and GSTP1 and the effect of diet and ***: With consents, genotypes of the genes were determined using PCR methods for 727 cases and 736sex and age-matched healthy controls recruited at a medical center in the Northern Taiwan. Nurses who were blind to the study hypothesis conducted interviews with study participants for the information of socio-demographic variables, diet and ***: There was no significant association between GSTM1 genotypes and the disease. Men, not women, with GSTT1 null genotype were at significant risk of colorectal cancer, but limited to rectal tumor, and in men aged 60 years and less. The corresponding association with the GSTP1 with G allele compared to GSTP1 A/A genotype was at borderline significance. Compared to men with GSTT1 present and GSTP1 A/A combined, men with both GSTT1 null and GSTP1 with G allele genotypes were at significant risk (odds ratio (OR) = 1.91, 95% confidence interval (CI) = 1.21-3.02), also limited to the rectal tumor and younger men. The beneficial effects of vegetable/fruit intake on colorectal cancer were much higher for men with GSTT1 present (OR = 0.32, 95%CI = 0.20-0.50) or GSTP1 A/A genotypes (OR = 0.40, 95%CI = 0.25-0.64).These effects remained significant for women. But, the greatest protective effect from vegetable/fruit intake for women was observed in those with GSTT1 null or GSTP1 with G allele genotypes. In addition, non-smoking men benefitted significantly from combined effect of higher vegetable/fruit intake and GSTT1 present or GSTP1 A/A genotypes with OR = 0.17 and 0.21 ***: This study suggests that the GSTT1 gene can modulate the colorectal cancer risk and vegetable/fruit-related colorectal cancer risk, particularly in men of no smoking history.

关键词： Colorectal cancer Glutathione S-transferase Polymorphisms Vegetables Smoking

Drone for Dynamic Monitoring and Tracking with Intelligent Image Analysis

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Intelligent Automation & Soft Computing 2023年第5期36卷 2233-2252页

作者： ching-Bang Yao chang-Yi Kao Jiong-Ting Lin Chinese Culture University TaipeiTaiwan Soochow University TaipeiTaiwan

Traditional monitoring systems that are used in shopping malls or com-munity management,mostly use a remote control to monitor and track speciﬁc objects;therefore,it is often impossible to effectively monitor the entire ***ﬁnding a suspicious person,the tracked object cannot be locked in time for *** research replaces the traditionalﬁxed-point monitor with the intelligent drone and combines the image processing technology and automatic judgment for the movements of the monitored *** intelligent system can effectively improve the shortcomings of low efﬁciency and high cost of the traditional monitor *** this article,we proposed a TIMT(The Intel-ligent Monitoring and Tracking)algorithm which can make the drone have smart surveillance and tracking *** combined with Artiﬁcial Intelligent(AI)face recognition technology and the OpenPose which is able to monitor the phy-sical movements of multiple people in real time to analyze the meaning of human body movements and to track the monitored intelligently through the remote con-trol interface of the *** system is highly agile and could be adjusted immediately to any angle and screen that we ***,the system couldﬁnd abnormal conditions immediately and track and monitor them *** is the system can immediately detect when someone invades the home or community,and the drone can automatically track the intruder to achieve that the two signiﬁcant shortcomings of the traditional monitor will be *** results show that the intelligent monitoring and tracking drone sys-tem has an excellent performance,which not only dramatically reduces the num-ber of monitors and the required equipment but also achieves perfect monitoring and tracking.

关键词： Drone deep learning face detection human pose intention equidistant track remote monitoring

Atomically dispersed catalysts for small molecule electrooxidation in direct liquid fuel cells

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Journal of Energy Chemistry 2022年第5期31卷 439-453页

作者： Jinfa chang Guanzhi Wang wei Zhang Yang Yang NanoScience Technology Center University of Central FloridaOrlandoFL 32826USA Department of Materials Science and Engineering University of Central FloridaOrlandoFL 32826USA Department of Chemistry Renewable Energy and Chemical Transformation ClusterUniversity of Central FloridaOrlandoFL 32826USA

Direct liquid fuel cells(DLFCs) have received increasing attention because of their high energy densities,instant recharging abilities, simple cell structure, and facile storage and transport. The main challenge for the commercialization of DLFCs is the high loading requirement of platinum group metals(PGMs) as catalysts. Atomically dispersed catalysts(ADCs) have been brought into recent focus for DLFCs due to their well-defined active sites, high selectivity, maximal atom-utilization, and anti-poisoning property. In this review, we summarized the structure–property relationship for unveiling the underlying mechanisms of ADCs for DLFCs. More specifically, different types of fuels used in DLFCs such as methanol, formic acid,and ethanol were discussed. At last, we highlighted current challenges, research directions, and future outlooks towards the practical application of DLFCs.

关键词： Atomic dispersion Electrocatalyst Small molecule electrooxidation Direct liquid fuel cells